Description from Flora of China
Chavica Miquel; Pothomorphe Miquel.
Shrubs or climbers, rarely herbs or small trees, aromatic. Stems thickened at nodes; outer vascular bundles in a ring, inner bundles scattered in 1 or 2 series. Prophylls present, often ± connate to petiole, caducous, forming a prominent, ringlike stipular scar at each node; main lateral veins all basal or partly pinnate. Flowers mostly unisexual, dioecious, less often monoecious or bisexual, sessile. Inflorescences leaf-opposed or rarely terminal spikes, rarely spikes grouped in an apparently axillary umbel; bracts small, sometimes adnate to rachis, often peltate. Stamens 2-6, usually on rachis, rarely at base of ovary; anthers 2-loculed, 2-4-lobed. Ovary distinct or sometimes immersed in rachis; ovule 1; stigmas (2 or)3-5. Fruit a drupe, sessile or stalked, often red or yellow, obovoid, ovoid, globose, or obovoid to cuneate-obovoid and laterally compressed, rarely ellipsoid, usually glabrous.
Variously estimated to include 1000-2000 species: mainly in tropical regions; 60 species (34 endemic, three introduced) in China.
F. B. Forbes & W. B. Hemsley (J. Linn. Soc., Bot. 36: 501. 1905) included Piper ferriei C. de Candolle and P. harmandii C. de Candolle in a list of additions to the flora of China, but no specimens were listed and none has been seen from China, so these species are excluded from this account. There are probably a few more Chinese species to be identified.
The following key is based primarily on fruiting material. Male inflorescences are collected much less often than the longer-lived and often much more prominent female spikes and are completely unknown in seven species. The leaves on climbing stems are often broader than those on flowering stems, with a thinner indumentum and with a tendency to have all the main veins arising basally.